Is it possible to hide menus

I would like to know if its possible to hide specific menus until a user logs in.

Yes, the easiest way do do this would be with Layouts. You can add a "Visibility condition" to the menu block that checks a User's role. 

Start on the Layouts UI at admin/structure/layouts, and click "Manage Blocks" for the default layout.

For whichever menu you'd like to hide, click on the "Configure" link at the right.

When the modal opens, csroll down to the "Visibility conditions" section at the very bottom, and pop it open. Click on "Add visibility condition"

Then select the User: role option.

Then select the user role "Authenticated" if you only want people who are logged-in to see the menu!

 

Note that you will need to repeat these steps for all layouts where you want the block limited by role.